1. Field of the Invention
This invention relates generally to an aftermarket plug-in or dealer retrofit device providing vehicle wireless communications and, more particularly, to an aftermarket plug-in device that can be coupled to a vehicle's on-board diagnostic (OBD) connector or another accessible location to provide vehicle-to-vehicle (V2V), vehicle-to-infrastructure (V2I) communications or vehicle-to-entity communications (V2X).
2. Discussion of the Related Art
Traffic accidents and roadway congestion are significant problems for vehicle travel. Vehicular ad-hoc network (VANET) based active safety and driver assistance systems, such as a dedicated short range communications (DSRC) system, known to those skilled in the art, allow a vehicle to transmit messages to other vehicles in a particular area with warning messages about dangerous road conditions, driving events, accidents, etc. In these systems, either direct broadcast communications or multi-hop geocast routing protocols, known to those skilled in the art, are commonly used to communicate warning messages, i.e., to deliver messages to vehicles that are within direct communication range or are located within a few kilometers from the road condition. In other words, an initial message advising drivers of a potential hazardous condition is transmitted from vehicle to vehicle either in a direct broadcast fashion or by using a geocast routing protocol so that vehicles within the desired application range will receive the messages of interest.
The communications systems referred to above include vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I) applications that require a minimum of one entity to send information to another entity. Broadly, short range communications that occur between a vehicle and any similarly equipped external object may be referred to as “V2X” communications. For example, many vehicle-to-vehicle safety applications can be executed on one vehicle by simply receiving broadcast messages from one or more neighboring vehicles. These messages are not directed to any specific vehicle, but are meant to be shared with a vehicle population to support the safety application. In these types of applications where collision avoidance is desirable, as two or more vehicles talk to one another and a collision becomes probable, the vehicle systems can warn the vehicle drivers, or possibly take action for the driver, such as applying the brakes. Likewise, roadway infrastructure components, such as traffic control units, can observe the information broadcasts or otherwise sense vehicle traffic and provide a driver warning if there is a detected hazard (e.g., if a vehicle is approaching a curve at an unsafe speed or there is a crossing vehicle that is violating a red traffic signal phase).
Since V2X communications is a cooperative technology, the system is dependent on other similarly equipped entities in order to provide safety benefits. As such, V2X systems are subject to the network effect, where the value of the system increases as the fleet penetration increases. In the early years of deployment, certain safety and other features may only be available in a limited fashion, as the number of communicating vehicles is not sufficient to provide safety benefits on a large scale. Existing vehicles without communications equipment will not be able to communicate with newer vehicles that have been deployed with a V2X communications system. Therefore, it may be desirable to provide an aftermarket device that is capable of being plugged into an existing vehicle to allow that vehicle to be capable of providing vehicle location and state information to other vehicles and enable a variety of V2X features on the host vehicle using location and state information that is obtained from other communicating vehicles.